In a small bowl, mix the softened butter, brown sugar, and cinnamon for the filling until smooth. Set it aside so it stays spreadable.

In a large mixing bowl, beat the softened butter and granulated sugar until creamy and light in texture. This step helps keep the cinnamon roll cookies soft.

Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract until fully combined.

In a separate bowl, whisk together the flour, baking soda, kosher salt, and cream of tartar.

Slowly add the dry ingredients into the wet mixture. Mix just until a soft dough forms. Do not overmix.

Place the dough on parchment paper and roll it into a rectangle about ¼-inch thick.

Spread the cinnamon filling evenly over the dough, leaving a small edge uncovered to help seal the roll.

Roll the dough tightly into a log, starting from the long side. Roll slowly to keep the cinnamon swirl neat.

Mix the rolling sugar and cinnamon in a small bowl. Roll the dough log in this mixture to coat the outside.

Wrap the log and chill for 20 minutes. This helps the cinnamon roll cookies slice clean.

Slice the chilled dough into even rounds and place them on a lined baking sheet.

Bake at 350°F for 10–12 minutes until the edges set and the centers stay soft. Cool for five minutes before serving.